xref: /linux/drivers/gpu/drm/tilcdc/tilcdc_panel.c (revision e0bf6c5ca2d3281f231c5f0c9bf145e9513644de)
1 /*
2  * Copyright (C) 2012 Texas Instruments
3  * Author: Rob Clark <robdclark@gmail.com>
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License version 2 as published by
7  * the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * You should have received a copy of the GNU General Public License along with
15  * this program.  If not, see <http://www.gnu.org/licenses/>.
16  */
17 
18 #include <linux/pinctrl/pinmux.h>
19 #include <linux/pinctrl/consumer.h>
20 #include <linux/backlight.h>
21 #include <linux/gpio/consumer.h>
22 #include <video/display_timing.h>
23 #include <video/of_display_timing.h>
24 #include <video/videomode.h>
25 
26 #include "tilcdc_drv.h"
27 
28 struct panel_module {
29 	struct tilcdc_module base;
30 	struct tilcdc_panel_info *info;
31 	struct display_timings *timings;
32 	struct backlight_device *backlight;
33 	struct gpio_desc *enable_gpio;
34 };
35 #define to_panel_module(x) container_of(x, struct panel_module, base)
36 
37 
38 /*
39  * Encoder:
40  */
41 
42 struct panel_encoder {
43 	struct drm_encoder base;
44 	struct panel_module *mod;
45 };
46 #define to_panel_encoder(x) container_of(x, struct panel_encoder, base)
47 
48 
49 static void panel_encoder_destroy(struct drm_encoder *encoder)
50 {
51 	struct panel_encoder *panel_encoder = to_panel_encoder(encoder);
52 	drm_encoder_cleanup(encoder);
53 	kfree(panel_encoder);
54 }
55 
56 static void panel_encoder_dpms(struct drm_encoder *encoder, int mode)
57 {
58 	struct panel_encoder *panel_encoder = to_panel_encoder(encoder);
59 	struct backlight_device *backlight = panel_encoder->mod->backlight;
60 	struct gpio_desc *gpio = panel_encoder->mod->enable_gpio;
61 
62 	if (backlight) {
63 		backlight->props.power = mode == DRM_MODE_DPMS_ON ?
64 					 FB_BLANK_UNBLANK : FB_BLANK_POWERDOWN;
65 		backlight_update_status(backlight);
66 	}
67 
68 	if (gpio)
69 		gpiod_set_value_cansleep(gpio,
70 					 mode == DRM_MODE_DPMS_ON ? 1 : 0);
71 }
72 
73 static bool panel_encoder_mode_fixup(struct drm_encoder *encoder,
74 		const struct drm_display_mode *mode,
75 		struct drm_display_mode *adjusted_mode)
76 {
77 	/* nothing needed */
78 	return true;
79 }
80 
81 static void panel_encoder_prepare(struct drm_encoder *encoder)
82 {
83 	struct panel_encoder *panel_encoder = to_panel_encoder(encoder);
84 	panel_encoder_dpms(encoder, DRM_MODE_DPMS_OFF);
85 	tilcdc_crtc_set_panel_info(encoder->crtc, panel_encoder->mod->info);
86 }
87 
88 static void panel_encoder_commit(struct drm_encoder *encoder)
89 {
90 	panel_encoder_dpms(encoder, DRM_MODE_DPMS_ON);
91 }
92 
93 static void panel_encoder_mode_set(struct drm_encoder *encoder,
94 		struct drm_display_mode *mode,
95 		struct drm_display_mode *adjusted_mode)
96 {
97 	/* nothing needed */
98 }
99 
100 static const struct drm_encoder_funcs panel_encoder_funcs = {
101 		.destroy        = panel_encoder_destroy,
102 };
103 
104 static const struct drm_encoder_helper_funcs panel_encoder_helper_funcs = {
105 		.dpms           = panel_encoder_dpms,
106 		.mode_fixup     = panel_encoder_mode_fixup,
107 		.prepare        = panel_encoder_prepare,
108 		.commit         = panel_encoder_commit,
109 		.mode_set       = panel_encoder_mode_set,
110 };
111 
112 static struct drm_encoder *panel_encoder_create(struct drm_device *dev,
113 		struct panel_module *mod)
114 {
115 	struct panel_encoder *panel_encoder;
116 	struct drm_encoder *encoder;
117 	int ret;
118 
119 	panel_encoder = kzalloc(sizeof(*panel_encoder), GFP_KERNEL);
120 	if (!panel_encoder) {
121 		dev_err(dev->dev, "allocation failed\n");
122 		return NULL;
123 	}
124 
125 	panel_encoder->mod = mod;
126 
127 	encoder = &panel_encoder->base;
128 	encoder->possible_crtcs = 1;
129 
130 	ret = drm_encoder_init(dev, encoder, &panel_encoder_funcs,
131 			DRM_MODE_ENCODER_LVDS);
132 	if (ret < 0)
133 		goto fail;
134 
135 	drm_encoder_helper_add(encoder, &panel_encoder_helper_funcs);
136 
137 	return encoder;
138 
139 fail:
140 	panel_encoder_destroy(encoder);
141 	return NULL;
142 }
143 
144 /*
145  * Connector:
146  */
147 
148 struct panel_connector {
149 	struct drm_connector base;
150 
151 	struct drm_encoder *encoder;  /* our connected encoder */
152 	struct panel_module *mod;
153 };
154 #define to_panel_connector(x) container_of(x, struct panel_connector, base)
155 
156 
157 static void panel_connector_destroy(struct drm_connector *connector)
158 {
159 	struct panel_connector *panel_connector = to_panel_connector(connector);
160 	drm_connector_unregister(connector);
161 	drm_connector_cleanup(connector);
162 	kfree(panel_connector);
163 }
164 
165 static enum drm_connector_status panel_connector_detect(
166 		struct drm_connector *connector,
167 		bool force)
168 {
169 	return connector_status_connected;
170 }
171 
172 static int panel_connector_get_modes(struct drm_connector *connector)
173 {
174 	struct drm_device *dev = connector->dev;
175 	struct panel_connector *panel_connector = to_panel_connector(connector);
176 	struct display_timings *timings = panel_connector->mod->timings;
177 	int i;
178 
179 	for (i = 0; i < timings->num_timings; i++) {
180 		struct drm_display_mode *mode = drm_mode_create(dev);
181 		struct videomode vm;
182 
183 		if (videomode_from_timings(timings, &vm, i))
184 			break;
185 
186 		drm_display_mode_from_videomode(&vm, mode);
187 
188 		mode->type = DRM_MODE_TYPE_DRIVER;
189 
190 		if (timings->native_mode == i)
191 			mode->type |= DRM_MODE_TYPE_PREFERRED;
192 
193 		drm_mode_set_name(mode);
194 		drm_mode_probed_add(connector, mode);
195 	}
196 
197 	return i;
198 }
199 
200 static int panel_connector_mode_valid(struct drm_connector *connector,
201 		  struct drm_display_mode *mode)
202 {
203 	struct tilcdc_drm_private *priv = connector->dev->dev_private;
204 	/* our only constraints are what the crtc can generate: */
205 	return tilcdc_crtc_mode_valid(priv->crtc, mode);
206 }
207 
208 static struct drm_encoder *panel_connector_best_encoder(
209 		struct drm_connector *connector)
210 {
211 	struct panel_connector *panel_connector = to_panel_connector(connector);
212 	return panel_connector->encoder;
213 }
214 
215 static const struct drm_connector_funcs panel_connector_funcs = {
216 	.destroy            = panel_connector_destroy,
217 	.dpms               = drm_helper_connector_dpms,
218 	.detect             = panel_connector_detect,
219 	.fill_modes         = drm_helper_probe_single_connector_modes,
220 };
221 
222 static const struct drm_connector_helper_funcs panel_connector_helper_funcs = {
223 	.get_modes          = panel_connector_get_modes,
224 	.mode_valid         = panel_connector_mode_valid,
225 	.best_encoder       = panel_connector_best_encoder,
226 };
227 
228 static struct drm_connector *panel_connector_create(struct drm_device *dev,
229 		struct panel_module *mod, struct drm_encoder *encoder)
230 {
231 	struct panel_connector *panel_connector;
232 	struct drm_connector *connector;
233 	int ret;
234 
235 	panel_connector = kzalloc(sizeof(*panel_connector), GFP_KERNEL);
236 	if (!panel_connector) {
237 		dev_err(dev->dev, "allocation failed\n");
238 		return NULL;
239 	}
240 
241 	panel_connector->encoder = encoder;
242 	panel_connector->mod = mod;
243 
244 	connector = &panel_connector->base;
245 
246 	drm_connector_init(dev, connector, &panel_connector_funcs,
247 			DRM_MODE_CONNECTOR_LVDS);
248 	drm_connector_helper_add(connector, &panel_connector_helper_funcs);
249 
250 	connector->interlace_allowed = 0;
251 	connector->doublescan_allowed = 0;
252 
253 	ret = drm_mode_connector_attach_encoder(connector, encoder);
254 	if (ret)
255 		goto fail;
256 
257 	drm_connector_register(connector);
258 
259 	return connector;
260 
261 fail:
262 	panel_connector_destroy(connector);
263 	return NULL;
264 }
265 
266 /*
267  * Module:
268  */
269 
270 static int panel_modeset_init(struct tilcdc_module *mod, struct drm_device *dev)
271 {
272 	struct panel_module *panel_mod = to_panel_module(mod);
273 	struct tilcdc_drm_private *priv = dev->dev_private;
274 	struct drm_encoder *encoder;
275 	struct drm_connector *connector;
276 
277 	encoder = panel_encoder_create(dev, panel_mod);
278 	if (!encoder)
279 		return -ENOMEM;
280 
281 	connector = panel_connector_create(dev, panel_mod, encoder);
282 	if (!connector)
283 		return -ENOMEM;
284 
285 	priv->encoders[priv->num_encoders++] = encoder;
286 	priv->connectors[priv->num_connectors++] = connector;
287 
288 	return 0;
289 }
290 
291 static const struct tilcdc_module_ops panel_module_ops = {
292 		.modeset_init = panel_modeset_init,
293 };
294 
295 /*
296  * Device:
297  */
298 
299 /* maybe move this somewhere common if it is needed by other outputs? */
300 static struct tilcdc_panel_info *of_get_panel_info(struct device_node *np)
301 {
302 	struct device_node *info_np;
303 	struct tilcdc_panel_info *info;
304 	int ret = 0;
305 
306 	if (!np) {
307 		pr_err("%s: no devicenode given\n", __func__);
308 		return NULL;
309 	}
310 
311 	info_np = of_get_child_by_name(np, "panel-info");
312 	if (!info_np) {
313 		pr_err("%s: could not find panel-info node\n", __func__);
314 		return NULL;
315 	}
316 
317 	info = kzalloc(sizeof(*info), GFP_KERNEL);
318 	if (!info) {
319 		pr_err("%s: allocation failed\n", __func__);
320 		of_node_put(info_np);
321 		return NULL;
322 	}
323 
324 	ret |= of_property_read_u32(info_np, "ac-bias", &info->ac_bias);
325 	ret |= of_property_read_u32(info_np, "ac-bias-intrpt", &info->ac_bias_intrpt);
326 	ret |= of_property_read_u32(info_np, "dma-burst-sz", &info->dma_burst_sz);
327 	ret |= of_property_read_u32(info_np, "bpp", &info->bpp);
328 	ret |= of_property_read_u32(info_np, "fdd", &info->fdd);
329 	ret |= of_property_read_u32(info_np, "sync-edge", &info->sync_edge);
330 	ret |= of_property_read_u32(info_np, "sync-ctrl", &info->sync_ctrl);
331 	ret |= of_property_read_u32(info_np, "raster-order", &info->raster_order);
332 	ret |= of_property_read_u32(info_np, "fifo-th", &info->fifo_th);
333 
334 	/* optional: */
335 	info->tft_alt_mode      = of_property_read_bool(info_np, "tft-alt-mode");
336 	info->invert_pxl_clk    = of_property_read_bool(info_np, "invert-pxl-clk");
337 
338 	if (ret) {
339 		pr_err("%s: error reading panel-info properties\n", __func__);
340 		kfree(info);
341 		of_node_put(info_np);
342 		return NULL;
343 	}
344 	of_node_put(info_np);
345 
346 	return info;
347 }
348 
349 static int panel_probe(struct platform_device *pdev)
350 {
351 	struct device_node *bl_node, *node = pdev->dev.of_node;
352 	struct panel_module *panel_mod;
353 	struct tilcdc_module *mod;
354 	struct pinctrl *pinctrl;
355 	int ret;
356 
357 	/* bail out early if no DT data: */
358 	if (!node) {
359 		dev_err(&pdev->dev, "device-tree data is missing\n");
360 		return -ENXIO;
361 	}
362 
363 	panel_mod = devm_kzalloc(&pdev->dev, sizeof(*panel_mod), GFP_KERNEL);
364 	if (!panel_mod)
365 		return -ENOMEM;
366 
367 	bl_node = of_parse_phandle(node, "backlight", 0);
368 	if (bl_node) {
369 		panel_mod->backlight = of_find_backlight_by_node(bl_node);
370 		of_node_put(bl_node);
371 
372 		if (!panel_mod->backlight)
373 			return -EPROBE_DEFER;
374 
375 		dev_info(&pdev->dev, "found backlight\n");
376 	}
377 
378 	panel_mod->enable_gpio = devm_gpiod_get(&pdev->dev, "enable");
379 	if (IS_ERR(panel_mod->enable_gpio)) {
380 		ret = PTR_ERR(panel_mod->enable_gpio);
381 		if (ret != -ENOENT) {
382 			dev_err(&pdev->dev, "failed to request enable GPIO\n");
383 			goto fail_backlight;
384 		}
385 
386 		/* Optional GPIO is not here, continue silently. */
387 		panel_mod->enable_gpio = NULL;
388 	} else {
389 		ret = gpiod_direction_output(panel_mod->enable_gpio, 0);
390 		if (ret < 0) {
391 			dev_err(&pdev->dev, "failed to setup GPIO\n");
392 			goto fail_backlight;
393 		}
394 		dev_info(&pdev->dev, "found enable GPIO\n");
395 	}
396 
397 	mod = &panel_mod->base;
398 	pdev->dev.platform_data = mod;
399 
400 	tilcdc_module_init(mod, "panel", &panel_module_ops);
401 
402 	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
403 	if (IS_ERR(pinctrl))
404 		dev_warn(&pdev->dev, "pins are not configured\n");
405 
406 	panel_mod->timings = of_get_display_timings(node);
407 	if (!panel_mod->timings) {
408 		dev_err(&pdev->dev, "could not get panel timings\n");
409 		ret = -EINVAL;
410 		goto fail_free;
411 	}
412 
413 	panel_mod->info = of_get_panel_info(node);
414 	if (!panel_mod->info) {
415 		dev_err(&pdev->dev, "could not get panel info\n");
416 		ret = -EINVAL;
417 		goto fail_timings;
418 	}
419 
420 	mod->preferred_bpp = panel_mod->info->bpp;
421 
422 	return 0;
423 
424 fail_timings:
425 	display_timings_release(panel_mod->timings);
426 
427 fail_free:
428 	tilcdc_module_cleanup(mod);
429 
430 fail_backlight:
431 	if (panel_mod->backlight)
432 		put_device(&panel_mod->backlight->dev);
433 	return ret;
434 }
435 
436 static int panel_remove(struct platform_device *pdev)
437 {
438 	struct tilcdc_module *mod = dev_get_platdata(&pdev->dev);
439 	struct panel_module *panel_mod = to_panel_module(mod);
440 	struct backlight_device *backlight = panel_mod->backlight;
441 
442 	if (backlight)
443 		put_device(&backlight->dev);
444 
445 	display_timings_release(panel_mod->timings);
446 
447 	tilcdc_module_cleanup(mod);
448 	kfree(panel_mod->info);
449 
450 	return 0;
451 }
452 
453 static struct of_device_id panel_of_match[] = {
454 		{ .compatible = "ti,tilcdc,panel", },
455 		{ },
456 };
457 
458 struct platform_driver panel_driver = {
459 	.probe = panel_probe,
460 	.remove = panel_remove,
461 	.driver = {
462 		.owner = THIS_MODULE,
463 		.name = "panel",
464 		.of_match_table = panel_of_match,
465 	},
466 };
467 
468 int __init tilcdc_panel_init(void)
469 {
470 	return platform_driver_register(&panel_driver);
471 }
472 
473 void __exit tilcdc_panel_fini(void)
474 {
475 	platform_driver_unregister(&panel_driver);
476 }
477